<SEC-DOCUMENT>0001051470-17-000004.txt : 20170104
<SEC-HEADER>0001051470-17-000004.hdr.sgml : 20170104
<ACCEPTANCE-DATETIME>20170104171538
ACCESSION NUMBER:		0001051470-17-000004
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20170101
FILED AS OF DATE:		20170104
DATE AS OF CHANGE:		20170104

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CROWN CASTLE INTERNATIONAL CORP
		CENTRAL INDEX KEY:			0001051470
		STANDARD INDUSTRIAL CLASSIFICATION:	REAL ESTATE INVESTMENT TRUSTS [6798]
		IRS NUMBER:				760470458
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1220 AUGUSTA DRIVE
		STREET 2:		SUITE 600
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77057
		BUSINESS PHONE:		7135703000

	MAIL ADDRESS:	
		STREET 1:		1220 AUGUSTA DRIVE
		STREET 2:		SUITE 600
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77057

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Collins Robert Sean
		CENTRAL INDEX KEY:			0001590197

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-16441
		FILM NUMBER:		17506913

	MAIL ADDRESS:	
		STREET 1:		C/O ALCOA UPSTREAM CORPORATION
		STREET 2:		390 PARK AVENUE
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022-4608
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>wf-form3_148356811807919.xml
<DESCRIPTION>FORM 3
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0206</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2017-01-01</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001051470</issuerCik>
        <issuerName>CROWN CASTLE INTERNATIONAL CORP</issuerName>
        <issuerTradingSymbol>CCI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001590197</rptOwnerCik>
            <rptOwnerName>Collins Robert Sean</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1220 AUGUSTA DRIVE SUITE 600</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77057</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Vice President and Controller</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Time RSUs</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0.0</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>3650.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Each Restricted Stock Unit (&quot;RSU&quot;) is issued pursuant to the Company's 2013 Long-Term Incentive Plan and represents a contingent right to receive one share of common stock, and vesting (i.e., forfeiture restriction termination) generally is subject to (i) the reporting person remaining an employee or director of the Company or its affiliates and (ii) the other criteria described in the footnote below.</footnote>
        <footnote id="F2">33 1/3% of the Time RSUs vest on December 12 of each of 2017, 2018 and 2019.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Robert Sean Collins</signatureName>
        <signatureDate>2017-01-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
